The object of the present invention is the disclosure of a method and apparatus for the manufacture of metallic sheet stock having ribs and the structure obtained thereby.
The invention pertains to the art of metalworking without substantial removal of material.
In bodywork, metalwork and building, upstanding ribbed or corrugated metallic structures are currently used in panels, racks, vans, containers, doors, portals, shelters and other articles and devices.
Such metal sheet stock have one or more stiffening ribs or, conversely, grooves, according to the dimensions thereof, and are obtained from a roll of material, by successive operations such as peeling, planing, cutting, press folding, etc.
At this time, in this type of structure, the ribs or grooves are longitudinally executed on the entire surface of the sheet, in other words they may be said to open on both sides of the structure.
In certain uses, structures which are assembled together have their ribs opening to the outside. These openings can receive all sorts of objects which are placed therein; water, snow, and dust can slip in and damage the material with time.
It has been heretofore proposed to plug such openings, but that necessitates a costly complementary operation which can destroy the esthetic factor and which slows the production of the work. One other method of plugging the grooves would be difficult due to the fact that it would be necessary to use enormous and very powerful presses.